1. Field of Invention
This invention relates generally to RFID tags and labels and, more particularly, to RFID tags and labels that have both RFID information and optically readable information.
2. Related Art
Typically, products stored in containers, such as cartons, boxes, and wrappers, are identified by a label on the outside of the container. Identifying information may also be printed directly onto the container with inkjet or any other suitable printing technology. The label may have optically readable information, such as a UPC barcode. These labels enable optical readers using a laser beam to scan the information contained thereon, such as description, price, date packaged, or any other usable data. One disadvantage of optically readable labels is that the optical reader and the label must be within a specific spatial relationship to each other, such as within a line of sight or along a perpendicular scan direction, or within a limited range to the optical reader.
A more recent type of label uses RFID or Radio Frequency Identification tags to store information. RFID uses radio frequency signals to acquire data from RFID tags within range of an RFID reader. RFID transponders or tags, either active or passive, are typically used with the RFID reader to read information from the RFID tag embedded in a label. RFID tags and labels can be obtained through companies such as Alien Technology Corporation of Morgan Hill, Calif. For passive tags, a typical RFID reader/writer energizes transponder circuitry in the tag by transmitting a power signal. The power signal may convey data, which can be stored in a transponder memory, or the transponder circuitry may transmit a response signal containing data previously stored in its memory. If the transponder circuitry transmits a response signal, the RFID reader/writer receives the response signal and interprets the stored data. The data is then transmitted to a host computer for processing.
One advantage of RFID labels is that line of sight is no longer required to read the label. This is a significant advantage since with barcodes, anything blocking the laser beam from the barcode would prevent the barcode from being read. Using radio frequencies enables RFID labels to be read even when line of sight is not present between the RFID label and the RFID reader. As the cost and size of RFID tags decrease, an ever-increasing number of companies and groups are favoring or requiring RFID labels on their products.
Even with a growing trend toward RFID labels, there are advantages to placing optical information on a label so that the package has both optical and RFID information, such as having the ability to read the label using more than one technology. This may be beneficial because RFID label technology is not as widespread as barcode technology, and many businesses or users may not have suitable RFID readers to read the RFID tag. Thus, it is desirable to have both RFID and optically readable information on a container.
However, it is crucial that the RFID label and the optically readable label contain information meant for or corresponding to the container. If the labels are mismatched, significant problems may arise, such as errors in tracking or maintaining information about the container. When both types of label are applied manually to the container, such as by line workers, the chance of mismatched labels increases due to human error. Furthermore, because RFID labels are structurally different from optically readable labels, e.g., the presence of an RFID tag embedded in the RFID label, many printers currently available print the RFID label and the optically readable label separately, either using the same printer system or separate printers. As a result, there is a greater likelihood that corresponding RFID labels and optically readable labels are not paired together. This increases the chances of having mismatched labels placed onto a container.
Therefore, there is a need for a combined RFID label and optically readable label and method of using the same that overcomes disadvantages of conventional methods discussed above.